Your location has been shared more than 5,000 times in the last two weeks

How much is your smartphone spying on you? Photo: Jim Merithew/Cult of Mac

Smartphone users know that sharing personal data with apps can be part of the price of free apps, but when it comes to how frequently those apps give that data to third parties, the numbers will shock you.

A new study by Carnegie Mellon found that some smartphone users’ data is shared more than 5,000 times with third parties in a two-week period. Most people are totally clueless this is happening, but the study found that when people learn how much frequently data is being shared, they act rapidly to shut down the spread of personal info.

During the course of the three-phase study, researchers collected app behavior data from 23 people using their own Android devices. On Android, users opt-in to location tracking when apps are downloaded. For iOS, it’s done on the device when it first attempts to use location. Still, many of the APIs developers use on the two platforms are very similar.

For the first week, candidates used their devices and apps like normal. During the second week, they were given access to AppsOps, to monitor the data those apps were sending. Then for the third phase, daily privacy notifications were sent to each participant detailing the frequency at which their sensitive information was accessed by apps.

Researchers found that app permission managers provided meaningful help to manage access to data. Participants checked their permissions 51 times and slammed 76 different apps with 272 permission restrictions. However, once permission changes were set, users rarely looked at them after a few days.

“App permission managers are better than nothing, but by themselves they aren’t sufficient,” said Norman Sadeh, a professor at Carnegie Mellon. “Privacy nudges can play an important role in increasing awareness and in motivating people to review and adjust their privacy settings.”

Once participants entered the third phase of the study, they began to received privacy nudges alerting them to the number of times apps shared their data, which led to an increase in blocking permission on apps. Sadeh says privacy notifications aren’t a silver bullet, though. Ultimately, his team of researchers hope to create software that can automatically configure your privacy settings for you, based on just a few privacy-related questions.